Faceting for subplots in R Programming - Cheat Sheet & Quick Revision

Recall & Review

beginner

What is faceting in R's ggplot2?

Faceting is a way to split data into subsets and create multiple plots (subplots) arranged in a grid, each showing a subset of the data.

beginner

Which ggplot2 function is used to create subplots by rows and columns?

The function facet_grid() is used to create subplots arranged by rows and columns based on one or two variables.

intermediate

How does facet_wrap() differ from facet_grid()?

facet_wrap() creates subplots wrapped into multiple rows or columns based on one variable, while facet_grid() arranges subplots in a strict grid by two variables (rows and columns).

intermediate

What does the syntax facet_grid(rows ~ cols) mean?

It means subplots are arranged with the variable for rows on the left side and the variable for columns on the right side of the tilde (~). For example, facet_grid(Species ~ .) creates rows by Species and one column.

beginner

Why use faceting instead of multiple separate plots?

Faceting helps compare subsets side-by-side in one combined plot, making patterns easier to see and saving space compared to separate plots.

Which function in ggplot2 creates subplots arranged in a grid by two variables?

A geom_point()

B facet_wrap()

C facet_grid()

D ggplot()

facet_grid() arranges subplots in a grid by rows and columns based on two variables.

What does facet_wrap(~ variable) do?

A Creates subplots wrapped by one variable

B Creates a single plot with no subplots

C Creates subplots arranged by two variables

D Removes facets from the plot

facet_wrap() splits data by one variable and wraps subplots into rows or columns.

In facet_grid(rows ~ cols), what does the tilde (~) separate?

A X and Y axis variables

B Rows variable and columns variable

C Plot title and subtitle

D Data and aesthetics

The tilde separates the variable for rows (left) and columns (right) in the grid layout.

Which of these is a benefit of faceting?

A Hide data points

B Make the plot slower to render

C Change plot colors automatically

D Compare subsets side-by-side in one plot

Faceting helps visually compare different subsets easily by showing them side-by-side.

If you want subplots only by rows and no columns, which syntax is correct?

A facet_grid(variable ~ .)

B facet_grid(. ~ variable)

C facet_wrap(~ variable)

D facet_grid(variable)

facet_grid(variable ~ .) creates subplots arranged by rows only.

Explain how faceting works in ggplot2 and when you would use facet_wrap() versus facet_grid().

Think about how you want to arrange your subplots: wrapped or in a grid.

Describe the syntax and meaning of facet_grid(rows ~ cols) and give an example.

Remember the tilde (~) separates rows and columns variables.